Nitrogen Flux in Jordan Lake:

Implications for Future Development

Hannah Aichelman, Mimi Caddell, Nikki Curnes,

Dan Huddleston, Austen Hughes, Abi Lee,

Alanna Marron and Katie Overbey

Spring 2014

Acknowledgements We would like to thank: • Jon Duncan

• Elizabeth Shay

• Trish D’Arconte (Stormwater Technician/Stream Ecologist, Town of Chapel Hill)

• UNC Institute for the Environment

• Philip McDaniel (GIS Librarian)

Outline

● Intro to Jordan Lake and Chatham Park

● Purpose of Capstone

● How We Approached the Problem ○ Sampling

○ Spatial Analysis

○ Flux Modeling

● Findings

● Suggestions for Future Projects

Jordan Lake

● Haw River

impounded in 1983

● Many important

functions

● Drinking water for

250,000 people

● Problems with

excess nutrients,

especially N

Effects of Excess N

Excess N from agriculture,

deposition and other human

activities

N runs off into

rivers and lakes...

Resulting in

Eutrophication...

...And hypoxic

conditions

JORDAN

LAKE

RULES

Jordan Lake Rules • Restore & maintain Jordan Lake’s many uses

• Best Management Practices

o Stormwater Rules

o Riparian Buffer Rules

o Wastewater Discharge Rules

o Agriculture Rules

o Fertilizer Management Rules

• 35% decrease of N for Orange County

• $600 million to implement

Image Source: DENR

Chatham Park

● Potential for changes in

nutrients

● Proposed by Preston

Development Company

● 7,000 acres for mixed-use,

residential, and R&D uses

● Projected population growth

of 60,000 people for

Pittsboro

Source: Town of Pittsboro, NC

Purpose of this Capstone

To provide preliminary baseline

estimations of changes in nitrogen fluxes

to Jordan Lake and its tributaries if

Chatham Park were developed.

Flux = Concentration * Discharge

• Field Sampling o 2 sites in Chapel Hill (existing data)

o 2 sites in Chatham Park (collected new data)

• Spatial Analysis o Delineate watersheds

o Calculate land cover and land cover change

• Flux Modeling in All Sites

Methods

GIS

DEM Layer

Elevation Fill

Flow Direction

Flow Accumulation

Stream Beds Test Point

Watershed

Watershed Delineation Land Cover

NLCD

Clip NLCD

Reclassified NLCD

Extract NLCD

Land Cover Change

Clip NLCD 1992 Clip NLCD 2011

Reclassify

NLCD 1992

Reclassify

NLCD 2011

LC Change 1992-2011

Extract LC Change 1992-2011

Sample Site Watersheds

Land Cover, 1992

Land Cover, 2011

EGRET: Exploration and Graphics for RivEr Trends

How Data Was Extrapolated

Type of Data Location Extrapolated From

Discharge Cane Creek

Concentration Piedmont Forest, MD

Extrapolated Chatham Park Data

Sampling Sites

Robeson Creek

Chatham Park

Morgan Creek

Chapel Hill

Stinking Creek

Chatham Park

Cane Creek

Chapel Hill

Cane Creek Morgan

Creek

Stinking Creek Robeson Creek

3/30/2014 3/30/2014 3/23/2014 3/30/2014 3/23/2014 3/30/2014

Nitrate (mg/L) 0.26 0.33 BDL* BDL* 1.2 0.54

Kjeldahl Nitrogen, TKN

(mg/L)

0.55 0.27 BDL* BDL* BDL* 0.57

Baseline Sampling Results

BDL = Below Detection Limit

*Nitrate detection limit: .1 mg/L

*TKN detection limit: .25 mg/L

• Goals for future projects: ○ Discharge data

○ More sampling sites

○ Long term monitoring

This project serves as a baseline analysis and guide for future work

Conclusions and Suggestions

• Goals for future projects: ○ Discharge data

○ More sampling sites

○ Long term monitoring

This project serves as a baseline analysis and guide for future work

QUESTIONS?

Conclusions and Suggestions

Bibliography 1. Baker, L. A., Hope, D., Yu, X., Edmonds, J., & Lauver, L. (2001). Nitrogen Balance for the Central Arizona–Phoenix (CAP) Ecosystem.

Retrieved from https://sakai.unc.edu/access/content/group/56067433-4b7d-4e25-9b9d-7552762c0705/Project%20folders--

materials%2C%20documents%2C%20tools/Jordan%20Lake%20nutrients/Baker_et_al2001.pdf

2. Chiosso, E. (n.d.). Haw Riverkeeper. Retrieved from http://hawriver.org/wp-content/uploads/2013/10/Water-Issues-Chatham-Park.pdf

3. Gu, B., Dong, X., Peng, C., Luo, W., Chang, J., & Ge, Y. (2012). The Long-Term Impact of Urbanization on Nitrogen Patterns and

Dynamics in Shanghai, China. Science Direct, 171, 30–37.

4. Pittsboro, NC (2012). http://www.city-data.com/city/Pittsboro-North-Carolina.html

5. "Chatham Park: A 7,000+ Acre Planned Live-Work-Play Community." Chatham Economic Development Corporation. N.p., n.d. Web. 24

Apr. 2014.

6. "NC-Culture – Sanford, NC Points of Interest, with a Special Thanks to Donald Pardue for Suggestions!" NCCulture. N.p., n.d. Web. 24

Apr. 2014.

7. Hirsch, Robert M., Douglas L. Moyer, and Stacey A. Archfield. "Weighted Regressions on Time, Discharge, and Season (WRTDS), with an

Application to Chesapeake Bay River Inputs1." JAWRA Journal of the American Water Resources Association 46.5 (2010): 857-880.

8. All images from slide 5 taken from Wikimedia Commons

EGRET Equation